This is a note to let you know that I've just added the patch titled iwlwifi: pcie: mark command queue lock with separate lockdep class to the 4.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: iwlwifi-pcie-mark-command-queue-lock-with-separate-lockdep-class.patch and it can be found in the queue-4.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From faead41cc7213ccef5a58c1bf518ac24816fe8a6 Mon Sep 17 00:00:00 2001 From: Johannes Berg <johannes.berg@xxxxxxxxx> Date: Thu, 22 Sep 2016 10:31:41 +0200 Subject: iwlwifi: pcie: mark command queue lock with separate lockdep class From: Johannes Berg <johannes.berg@xxxxxxxxx> commit faead41cc7213ccef5a58c1bf518ac24816fe8a6 upstream. Emmanuel reports that when CMD_WANT_ASYNC_CALLBACK is used by mvm, the callback will be called with the command queue lock held, and mvm will try to stop all (other) TX queues, which acquires their locks - this caused a false lockdep recursive locking report. Suppress this report by marking the command queue lock with a new, separate, lock class so lockdep can tell the difference between the two types of queues. Fixes: 156f92f2b471 ("iwlwifi: block the queues when we send ADD_STA for uAPSD") Reported-by: Emmanuel Grumbach <emmanuel.grumbach@xxxxxxxxx> Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/wireless/intel/iwlwifi/pcie/tx.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/drivers/net/wireless/intel/iwlwifi/pcie/tx.c +++ b/drivers/net/wireless/intel/iwlwifi/pcie/tx.c @@ -522,6 +522,7 @@ error: static int iwl_pcie_txq_init(struct iwl_trans *trans, struct iwl_txq *txq, int slots_num, u32 txq_id) { + struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); int ret; txq->need_update = false; @@ -536,6 +537,13 @@ static int iwl_pcie_txq_init(struct iwl_ return ret; spin_lock_init(&txq->lock); + + if (txq_id == trans_pcie->cmd_queue) { + static struct lock_class_key iwl_pcie_cmd_queue_lock_class; + + lockdep_set_class(&txq->lock, &iwl_pcie_cmd_queue_lock_class); + } + __skb_queue_head_init(&txq->overflow_q); /* Patches currently in stable-queue which might be from johannes.berg@xxxxxxxxx are queue-4.8/iwlwifi-pcie-mark-command-queue-lock-with-separate-lockdep-class.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html